iconphoto() method in Tkinter | Python

iconphoto() method is used to set the titlebar icon of any tkinter/toplevel window. But to set any image as the icon of titlebar, image should be the object of PhotoImage class.
Syntax: 

iconphoto(self, default = False, *args)

Steps to set icon image –

from tkinter import Tk
master = Tk()

photo = PhotoImage(file = "Any image file")
master.iconphoto(False, photo)

Set the titlebar icon for this window based on the named photo images passed through args. If default is True, this is applied to all future created toplevels as well. The data in the images is taken as a snapshot at the time of invocation. If the images are later changed, this is not reflected in the titlebar icons. The function also scales provided icons to an appropriate size.
Code #1: When PhotoImage is provided. 

Python3

# Importing Tkinter module
from tkinter import *
from tkinter.ttk import *

# Creating master Tkinter window
master = Tk()

# Creating object of photoimage class
# Image should be in the same folder
# in which script is saved
p1 = PhotoImage(file = 'info.png')

# Setting icon of master window
master.iconphoto(False, p1)

# Creating button
b = Button(master, text = 'Click me !')
b.pack(side = TOP)

# Infinite loop can be terminated by
# keyboard or mouse interrupt
# or by any predefined function (destroy())
mainloop()

Output:

Exception: If you provide an image directly instead of PhotoImage object then it will show the following error.
Code #2: When PhotoImage object is not provided. 

Python3

# Importing Tkinter module
from tkinter import *
from tkinter.ttk import *

# Creating master Tkinter window
master = Tk()

# Setting icon of master window
master.iconphoto(False, 'info.png')

# Creating button
b = Button(master, text = 'Click me !')
b.pack(side = TOP)

# Infinite loop can be terminated by
# keyboard or mouse interrupt
# or by any predefined function (destroy())
mainloop()

Output:

Traceback (most recent call last):
  File "C:\Users\Admin\Documents\GUI_python\geeks.py", line 14, in 
    master.iconphoto(False, 'info.png')
  File "C:\Users\Admin\AppData\Local\Programs\Python\Python37-32\lib\tkinter\__init__.py", line 1910, in wm_iconphoto
    self.tk.call('wm', 'iconphoto', self._w, *args)
_tkinter.TclError: can't use "info.png" as iconphoto: not a photo image